nycrhythm — NYC Subway Live Map

Open a tab, watch New York breathe. Every train in the NYC subway, moving live on the map — powered by MTA GTFS-Realtime.

Live: https://nycrhythm.scottchen0622.com

Sister project of mrtrhythm (Taipei Metro,「捷奏」) — same engine philosophy. Taipei simulates schedules and calibrates against arrival boards; New York reads true per-train positions from GTFS-RT. Two cities, one rhythm.

How it works

• Data pipeline (pipeline/, daily via GitHub Actions): MTA GTFS static → network.json (29 routes, 496 stations + transfer complexes, 257 track-shape variants with per-stop chainage). No API key required.
• RT proxy (api/rt): decodes 8 GTFS-RT protobuf feeds, slims to JSON, edge-cached 15s — MTA load is decoupled from visitor count.
• Engine (web/): each train is interpolated along official track geometry between its own real-time stop predictions. Follow mode, station arrival boards (transfer-complex aware), search, deep links, your GPS position with compass heading (📍, on-device only). Auto day/night follows the NYC sun.

Develop

npm install
npm run dev        # local dev (RT via production API)
npm run build
npx tsx pipeline/build-network.ts   # rebuild network.json from GTFS zip

Docs & phase plans (PDCA, in Chinese): PRD.md · SDD.md · plans/ · BACKLOG.md

Data & License

• Data: MTA Open Data — GTFS static + GTFS-Realtime (key-free)
• Basemap: © OpenStreetMap © CARTO
• Code: MIT